WPF通过条件以编程方式更改行背景色

Question

I am trying to use LoadingRow for change row colors programatically. It is working as i need. But the problem is with scrollbar. When i use the scrollbar in datagrid my formula is running again and i am getting silly ordered row colors.

here is my code. i am trying to change colors with 17th columns value.

        private void dataGrid1_LoadingRow(object sender, DataGridRowEventArgs e)
    {
        DataGridRow row = e.Row;
        DataRowView rView = row.Item as DataRowView;
        if (rView != null && rView.Row.ItemArray[17].ToString().Contains("1"))
        {
            renk++;  
        }
        if (renk % 2 == 0)
        {
            e.Row.Background = (SolidColorBrush)(new BrushConverter().ConvertFrom("#FF0000"));
        }
        else
        {
            e.Row.Background = (SolidColorBrush)(new BrushConverter().ConvertFrom("#ffffff"));
        }
    }

After running of my code it is working. But when i scrolling down my mouse to see following rows it is working also. Then when i scrolling up mouse to see first rows my code does'nt work good. You can see difference between opened time and after scrolling pictures below.

Thanks.

Answer 1

This should work if you turn off virtualization on the DataGrid :

<DataGrid
    EnableRowVirtualization="False"

It's reusing the DataGridRow objects for different rows. If you've got 10,000 rows and 30 are visible, it's silly to create 10,000 DataGridRow control objects. If you've got enough items, the above will bring your application to its knees. However, you may have a small number of items, in which case the above kludge is good enough.

But you don't need to do that in any case. The correct way to do it is to leave row virtualization enabled and work with WPF instead of against it, like the XAML below.

I don't know what your column 17 is called so I created a quickie table populated with fizz buzz items. My equivalent of your column 17 is a column named State . If you provide a little more information we can make this match what you're actually doing.

<DataGrid
    ItemsSource="{Binding FizzBuzzTable}"
    >
    <DataGrid.RowStyle>
        <Style TargetType="DataGridRow">
            <Style.Triggers>
                <DataTrigger Binding="{Binding State}" Value="Fizz">
                    <Setter Property="Background" Value="LightYellow" />
                </DataTrigger>
                <DataTrigger Binding="{Binding State}" Value="Buzz">
                    <Setter Property="Background" Value="LightSkyBlue" />
                </DataTrigger>
                <DataTrigger Binding="{Binding State}" Value="FizzBuzz">
                    <Setter Property="Background" Value="GreenYellow" />
                </DataTrigger>
            </Style.Triggers>
        </Style>
    </DataGrid.RowStyle>
</DataGrid>

Answer 2

can be easier with xaml as Datagrid as property for that

AlternationCount = 2

and the brush AlternatingRowBackground

Answer 3

You can also try

DataGrid.RowStyleSelector

removing virtualization is not good !